A virtual machine (VM) is computing entity that emulates a computer system, and may operate on any of several hardware platforms. A particular VM may operate on a first hardware platform during a first time slot and on a second hardware platform during a second time slot. That is, the VM may migrate between various physical platforms (“migratable VM”).
A trusted computing base (TCB) of a physical platform may include underlying virtualization infrastructure. For example, the TCB of a particular physical platform may include a processor, basic input-output system (BIOS), hypervisor, and virtualization helper virtual machines.